Method and apparatus for handling cell reselections and transitions to and from an enhanced cell_fach state

ABSTRACT

A method and apparatus for handling cell reselections and transitions includes executing a cell reselection. A medium access control (MAC)-ehs reset is performed.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/855,703, filed Sep. 16, 2015, which is a continuation of U.S. patentapplication Ser. No. 14/190,971, filed Feb. 26, 2014, now U.S. Pat. No.9,185,739, which is a continuation of U.S. patent application Ser. No.13/360,208, filed Jan. 27, 2012, now U.S. Pat. No. 8,705,491, which is acontinuation of U.S. application Ser. No. 12/112,097, filed Apr. 30,2008, now U.S. Pat. No. 8,130,724, which claims the benefit of U.S.Provisional Application Nos. 60/915,048, filed Apr. 30, 2007,60/944,661, filed Jun. 18, 2007, 60/944,540, filed Jun. 18, 2007, and60/955,578, filed Aug. 13, 2007, the contents of which are eachincorporated by reference as if fully set forth herein.

FIELD OF INVENTION

This application is related to wireless communications.

BACKGROUND

User equipments (UEs) in a universal telecommunications radio accessnetwork (UTRAN) are typically in either of two modes: Idle or Connected.Based on UE mobility and activity while in connected mode, the UTRAN candirect the UE to transition between a number of sub-states, such as cellpaging channel (Cell_PCH), UTRAN Registration Area Paging Channel(URA_PCH), cell forward access channel (Cell_FACH), and Cell_DCH. Thisis typically accomplished through a network based reconfigurationprocedure or as a result of a cell update procedure. The latter isinitiated by the UE to tell the network about its current location. TheCell_DCH state is characterized by dedicated channels in both the uplinkand the downlink. On the UE side, this corresponds to continuoustransmission and reception and can be demanding on user powerrequirements. The Cell_FACH state does not use dedicated channels andthus allows better power consumption, at the expense of a lower uplinkand downlink throughput.

Recent work by the standardization bodies has identified the possibilityof using High-Speed Downlink Packet Access (HSDPA) in Cell_FACH andCell/URA_PCH. HSDPA is a feature that was introduced in Release 5 of theThird Generation Partnership Project (3GPP) specifications to operate inCell_DCH. HSDPA tries to make better use of the downlink shared capacityby using concepts such as Adaptive Modulation and Coding (AMC),retransmissions using a Hybrid-ARQ (HARQ) scheme, and Node Bscheduling—all operating at a very fast rate. Packet data units (PDUs)are combined by the HARQ, and subsequently stored in a reordering queueto deal with possible out-of-order reception. Downlink transmissions areaddressed to a UE via an HS-DSCH Radio Network Identifier (H-RNTI).

It is assumed that if the UE supports HSDPA in Release 7, then it alsosupports HSDPA in CELL_FACH and in CELL/URA_PCH. HS-DSCH reception inCELL_FACH can be configured without HS-DSCH reception in CELL_PCH andURA_PCH. High speed downlink shared channel (HS-DSCH) reception inCELL_PCH and URA_PCH without the support of HS-DSCH reception inCELL_FACH is not supported. The UE support for these features issignaled to the network. It should be understood that the embodimentspresented can be extended to cases where the support for HSDPA inCELL_FACH and/or CELL_PCH/URA_PCH can be individually signaled to thenetwork.

On the other hand, the network signals its support for enhancedCELL_FACH via the System Information Block (SIB5/5bis). Two newinformation elements (IEs) have been introduced: “HS-DSCH common systeminformation”—indicating the HSDPA reception is supported for CELL_FACHstate; and “HS-DSCH paging system information”—indicating that HSDPAreception is supported for CELL/URA_PCH state.

To indicate whether HS-DSCH reception is ongoing in CELL_FACH, two newBoolean variables have been added: HS_DSCH_RECEPTION_CELL_FACH_STATE: IfTRUE indicates that HS_DSCH reception in CELL_FACH is ongoing; andHS_DSCH_RECEPTION_OF_CCCH_ENABLED: If TRUE indicates that HS-DSCHreception is enabled for CCCH. This variable is set to TRUE when the UEis using a common H-RNTI to receive HSDPA traffic, and is set to FALSEwhen the UE is not.

A UE is assigned a common H-RNTI to receive traffic when it has not beenassigned a dedicated H-RNTI. Three such situations are as follows:

-   -   1) UE sends a Radio Resource Control (RRC) CONNECTION REQUEST        message (and UE is waiting for an RRC CONNECTION SETUP response        from the network).    -   2) UE sends a CELL UPDATE message and is waiting for a CELL        UPDATE CONFIRM response from the network.    -   3) UE sends a URA UPDATE message and is waiting for a URA UPDATE        CONFIRM response from the network.

No new variable has been proposed for CELL/URA_PCH HS-DSCH receptionindication. When in CELL/URA_PCH, and if the IE “HS-DSCH paging systeminformation” is broadcast, the UE sets up HSDPA reception. In somecases, a UE will no longer be able to continue reception of high speedPDUs, (e.g., as a result of a hard handover, cell reselection, radiolink failure, and the like). In these cases, the MAC should be reset.The reset procedure allows the UE to forward all PDUs in the reorderingqueues up to higher layers, and to re-initialize all high speed statevariables.

In 3GPP Release 6, HSDPA was only supported in CELL_DCH. As a result,MAC resets, (e.g., a mac-hs reset) were performed under the followingconditions: the UE underwent a radio link failure, the UE experienced anRLC unrecoverable error, or the UE was ordered to transition to a statewhere HSDPA was not supported (all states except CELL DCH).

In Release 7, as currently defined, a UE may be required to perform aMAC reset in the following states: CELL_DCH, CELL_FACH, CELL/URA_PCH. Inaddition to the conditions specified above, (i.e., that apply to a UE inCELL DCH), the UE is required to perform a MAC reset after ALL cellreselections. Currently this is only done when the WTRU with a dedicatedH-RNTI performs a cell reselection. There are a number of scenarioswhere this reset is not performed, resulting in possible reorderingerrors.

Transitions to/from IDLE have also been impacted by the introduction ofEnhanced CELL_FACH. If a Release 7 UE supports HSDPA reception inCELL_FACH state, this UE also supports limited HSDPA reception while inIDLE mode; in particular after a UE has issued an RRC CONNECTIONREQUEST, and is waiting for an RRC CONNECTION SETUP message from thenetwork. Three issues have been identified:

-   -   1) If the UE has begun HSDPA reception while in IDLE (after        issuing a RRC CONNECTION SETUP message), any cell reselections        should result in a MAC reset.    -   2) If an RRC connection procedure is aborted, the UE should        clear all its HSDPA resources.    -   3) While in IDLE mode, a UE may cell reselect from a cell that        supports Enhanced CELL FACH to one that does not, and vice        versa. If the UE has initiated an RRC connection procedure, two        issues may need to be addressed. First, for a Release 6 to a        Release 7 transition, the UE is required to setup the HSDPA        resources so that it can receive the RRC CONNECTION SETUP        message on the HS-DSCH. Second, for a Release 7 to Release 6        transition, the UE should release all HSDPA resources, as no        traffic is expected on the HS-DSCH.

Another new feature of Enhanced CELL_FACH is that the UE will be able toreceive dedicated control messages while in CELL_PCH (over the DCCH).Accordingly, a UE may be asked to perform a reconfiguration, (e.g.,radio bearer, transport channel, physical channel). Reconfigurationmessages can also result in a state change.

In order to allow proper configuration of HSDPA resources the UE shouldproperly manage the setting or clearing of the variableHS_DSCH_RECEPTION_OF_CCCH_ENABLED to ensure that it is only set to TRUEwhen the UE is using the common H-RNTI while in an enhanced Cell_FACHstate. It should be set to FALSE in all other. Lastly, cell reselectionsoccurring during ongoing cell update or URA update procedures shouldbehave similarly to cell reselections when these procedures are notongoing.

It would therefore be beneficial to provide a method and apparatus forhandling cell reselections and transitions to and from an enhancedCELL_FACH state. cl SUMMARY

A method and apparatus for handling cell reselections, transitions, andCell_DCH radio link failures is disclosed. The method includes executinga cell reselection. A medium access control (MAC)-ehs reset isperformed.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding may be had from the following description,given by way of example in conjunction with the accompanying drawingswherein:

FIG. 1 shows an example wireless communication system including aplurality of wireless transmit/receive units (WTRUs) and a Node B;

FIG. 2 is an example functional block diagram of a WTRU and the Node Bof FIG. 1; and

FIG. 3 is a flow diagram of a method for handling cell reselections andtransitions to and from an enhanced CELL_FACH state.

DETAILED DESCRIPTION

When referred to hereafter, the terminology “wireless transmit/receiveunit (WTRU)” includes but is not limited to a user equipment (UE), amobile station, a fixed or mobile subscriber unit, a pager, a cellulartelephone, a personal digital assistant (PDA), a computer, or any othertype of user device capable of operating in a wireless environment. Whenreferred to hereafter, the terminology “base station” includes but isnot limited to a Node-B, a site controller, an access point (AP), or anyother type of interfacing device capable of operating in a wirelessenvironment.

When referred to hereafter, the terminology “Release 7 (R7)”, includesbut is not limited to a WTRU or Node B that supports HS-DSCH inCELL_FACH and/or CELL/URA_PCH and “Release 6 (R6)” includes but is notlimited to a WTRU or Node B that does not support HS-DSCH in CELL_FACHand/or CELL/URA_PCH.

HS-DSCH in CELL_FACH also includes HS-DSCH reception in idle mode forthe reception of RRC connection procedures.

When referred to hereafter, the terminology “enhanced CELL_FACH state”includes but is not limited to a WTRU that is using HSDPA resources in astate other than CELL_DCH.

FIG. 1 shows an example wireless communication system 100 including aplurality of WTRUs 110, a Node B 120, and a radio network controller(RNC) 130. As shown in FIG. 1, the WTRUs 110 are in communication withthe Node B 120, which is in communication with the RNC 130. It should benoted that, although an example configuration of WTRUs 110, Node B 120,and RNC 130 is depicted in FIG. 1, any combination of wireless and wireddevices may be included in the wireless communication system 100.

FIG. 2 is an example functional block diagram 200 of a WTRU 110 and theNode B 120 of the wireless communication system 100 of FIG. 1. As shownin FIG. 2, the WTRU 110 is in communication with the Node B 120. TheNode B 120 is configured to handle cell reselections and transitions toand from an enhanced Cell_FACH state.

In addition to the components that may be found in a typical WTRU, theWTRU 110 includes a processor 115, a receiver 116, a transmitter 117,and an antenna 118. The receiver 116 and the transmitter 117 are incommunication with the processor 115. The antenna 118 is incommunication with both the receiver 116 and the transmitter 117 tofacilitate the transmission and reception of wireless data. Theprocessor 115 of the WTRU 110 is configured to handle cell reselectionsand transitions to and from an enhanced Cell_FACH state.

In addition to the components that may be found in a typical Node B, theNode B 120 includes a processor 125, a receiver 126, a transmitter 127,and an antenna 128. The receiver 126 and the transmitter 127 are incommunication with the processor 125. The antenna 128 is incommunication with both the receiver 126 and the transmitter 127 tofacilitate the transmission and reception of wireless data.

FIG. 3 is a flow diagram of a method 300 for handling cell reselectionsout of an enhanced CELL_FACH state. Although specifics of the method 300will be described in greater detail below, in general, a WTRU 110executes a cell reselection (step 310). Upon executing the cellreselection, a medium access control (MAC)-ehs reset is performed (step320) due to the fact that the source of the HS-DSCH may have changed.Depending on the reselected cell, the WTRU 110 may clear HSDPA resourcesand stop HS-DSCH reception procedures.

In one example, the MAC-hs/ehs reset is performed when a cellreselection occurs while the WTRU 110 is waiting for aCELL_UPDATE_CONFIRM message. The reset may be performed in all casesupon cell reselection, (i.e., even when the WTRU does not have adedicated H-RNTI), or only when the WTRU has ongoing HSDPA reception,(i.e., when the WTRU is receiving HS-DSCH prior to cell reselection).

For example, if cell update/URA update timer expires or a reselection toanother UTRA cell occurs prior to completion of the cell update or URAupdate procedure, the WTRU 110 may detect “in service area” if it hasnot entered idle mode. In this case, if the cell update or URA updateprocedure counter is less than or equal to a maximum number ofretransmissions of the cell update/URA update message, then the WTRU 110may perform a cell reselection.

For frequency division duplex (FDD), for example, if the WTRU 110supports HS-DSCH reception and the information element (IE) “HS-DSCHcommon system information” is included in SIB5 or SIB5bis, then the WTRU110 may reset the MAC-ehs entity.

Alternatively, the WTRU 110 may, after performing cell selection, resetthe MAC-ehs entity after a radio link failure from CELL_DCH. As the WTRU110 may be using a common H-RNTI, rather than a dedicated H-RNTI, areset may allow reception of a new MAC flow, (e.g., for CCCH and SRB1).

For example, the WTRU 110 may initiate a cell update procedure as aresult of a radio link failure while in CELL_DCH. For FDD, if the WTRU110 supports HS-DSCH reception and the information element (IE) “HS-DSCHcommon system information” is included in SIB5 or SIB5bis, then the WTRU110 may reset the MAC-ehs entity.

Alternatively, the WTRU 110 may, after performing a cell reselectionwithout a dedicated H-RNTI, reset the MAC-ehs entity.

For example, the WTRU 110 may initiate a URA update or cell updateprocedure. If the WTRU 110 performed a cell reselection, then for FDD,if the WTRU 110 supports HS-DSCH reception and the information element(IE) “HS-DSCH common system information” is included in SIB5 or SIB5bis,then the WTRU 110 may reset the MAC-ehs entity.

WTRU 110 is allowed to use HS-DSCH reception in IDLE mode (such as aftertransmitting a RRC CONNECTION REQUEST). When the WTRU 110 transmits aRRC CONNECTION REQUEST, it monitors the downlink transmissions todetermine the RNC response. During this time the WTRU 110 may performcell reselections.

Depending on the reselected cell, the WTRU 110 may transition from acell that supports HSDPA reception in CELL_FACH and CELL/URA_PCH to onethat no longer supports HS-DSCH reception. The WTRU 110 may clear, orrelease HSDPA resources and stop HS-DSCH reception procedures.

For example, if the WTRU 110 has transmitted a RRC CONNECTION REQUESTand has not yet received an RRC CONNECTION SETUP message with the valueof the IE “Initial UE identity” equal to the value of the variableINITIAL_UE_IDENTITY, and if cell re-selection or expiry of RRCCONNECTION REQUEST timers (currently referred to in the standard as T300or T318) occurs, WTRU 110 may check that the RRC CONNECTION procedurecounter (currently referred to in the standard as V300) is less than orequal to the maximum number of retransmissions of the RRC CONNECTIONREQUEST message (currently referred to in the standard as N300), and ifcell reselection occurred, for FDD, and if the WTRU 110 supports HS-DSCHreception and if IE: “HS-DSCH common system information” is not includedin SIB5 or SIB5bis, then, the WTRU 110 may release HSDPA resources bystopping HS_SCCH and HS-DSCH reception procedures. Additionally, theWTRU 110 may clear the variable H_RNTI and remove any stored H-RNTI. Inaddition to resetting the MAC-ehs entity, the WTRU 110 may also releaseall HARQ resources.

Alternatively, the WTRU 110 may choose to perform the above only whenHSDPA resources are being used prior to cell reselection.

Also, the WTRU 110 actions can be triggered by using an existingHS_DSCH_RECEPTION variable, or a new HS_DSCH_RECEPTION variable may bedefined as a flag to denote HSDPA resource use, thereby triggering aresource release.

Depending on the reselected cell, the WTRU 110 may transition acrosscells that support HSDPA reception in CELL_FACH and CELL/URA_PCH. TheWTRU may perform a MAC-ehs reset.

For example, if the WTRU 110 has transmitted a RRC CONNECTION REQUESTand has not yet received an RRC CONNECTION SETUP message with the valueof the IE “Initial UE identity” equal to the value of the variableINITIAL_UE_IDENTITY, and if cell re-selection or expiry of RRCCONNECTION REQUST timers (T300 or T318) occurs, WTRU 110 may check thatthe RRC CONNECTION procedure counter (V300) is less than or equal to themaximum number of retransmissions of the RRC CONNECTION REQUEST message(N300), and if cell reselection occurred, for FDD, and if the WTRU 110supports HS-DSCH reception and if IE: “HS-DSCH common systeminformation” is included in SIB5 or SIB5bis, and if the variable“HS-DSCH_RECEPTION_OFF_CCCH_ENABLED” is set to TRUE, then, the WTRU 110may reset the MAC-ehs entity.

Depending on the reselected cell, the WTRU 110 may transition from acell that does not support HSDPA reception in CELL_FACH and CELL/URA_PCHto one that does support HS-DSCH reception. In such a case, the WTRU 110may be required to setup the HS-DSCH, (e.g., HARQ resources, commonH-RNTI, MAC flow for CCCH traffic, and the like).

In this situation, a number of scenarios may be utilized. For example,if the WTRU 110 has transmitted a RRC CONNECTION REQUEST and has not yetreceived an RRC CONNECTION SETUP message with the value of the IE“Initial UE identity” equal to the value of the variableINITIAL_UE_IDENTITY, and if cell re-selection or expiry of RRCCONNECTION REQUST timers (T300 or T318) occurs, WTRU 110 may check thatthe RRC CONNECTION procedure counter (V300) is less than or equal to themaximum number of retransmissions of the RRC CONNECTION REQUEST message(N300), and if cell reselection occurred, for FDD, and if the WTRU 110supports HS-DSCH reception and if IE: “HS-DSCH common systeminformation” is included in SIB5 or SIB5bis, and if the variable“HS-DSCH_RECEPTION_OFF_CCCH_ENABLED” is set to FALSE, then, the WTRU 110may set the variable “HS-DSCH_RECEPTION_OFF_CCCH_ENABLED” to TRUE, andstart receiving HS-DSCH.

Alternatively, a WTRU 110 in IDLE mode may set the CCCH flag to TRUE inan R6 cell. In order to guarantee that HS_DSCH_RECEPTION_OF_CCCH_ENABLEDis TRUE in an R6 cell the variable should be set to TRUE each time thesystem information is read in an R6 cell or anytime the WTRU 110 is inan R6 cell and transitions to IDLE mode from connected mode. This can beachieved by changing the actions when entering idle mode from connectedmode.

As another alternative, every time a WTRU 110 in IDLE mode with anongoing RRC connection procedure performs a cell reselection, the WTRU110 sets the CCCH flag to TRUE and then performs the actions related tothis variable. For example, the WTRU 110 may send an RRC CONNECTIONREQUEST message and be waiting for an RRC CONNECTION SETUP MESSAGE. Ifthere is a cell reselection, and the transition is from an R7 to R7cell, the MAC-ehs entity is reset only. If the transition is from an R6to R7 cell, the variable HS_DSCH_RECEPTION_OF_CCH_ENABLED is set to“true” and the WTRU 110 begins receiving the HS-DSCH. If the transistionis from an R7 to R6 cell, then HS_SCCH reception procedures are stopped,HS-DSCH reception procedures are stopped, the MAC-ehs entity is reset,HARQ resources are released, and store “HARQ info” IEs are cleared.

The variable HS_DSCH_RECEPTION_OF_CCCH_ENABLED is used as a flag todenote that the WTRU 110 is using a common H-RNTI. This variable shouldbe set to “FALSE” when the WTRU 110 is not using its common H-RNTI. Thismay ensure that evaluation of the variableHS_DSCH_RECEPTON_CELL_FACH_STATE will correctly clear resources onlywhen a dedicated H-RNTI is assigned to the WTRU 110. Receiving on thecommon H-RNTI is typically possible when the WTRU 110 has performed acell reselection and is waiting for the CELL UPDATE CONFIRM message, orwhen the WTRU 110 has performed a URA reselection and is waiting for theURA UPDATE CONFIRM message, or when the WTRU 110 has initiated an RRCsetup and is waiting for the RRC CONNECTION SETUP message.

After receiving an RRC CONNECTION SETUP message that will send the WTRU110 in the CELL_DCH state, then the WTRU 110 sets variableHS_DSCH_RECEPTION—OF_CCCH_ENABLED to “FALSE”.

The WTRU 110 may terminate activities associated with CELL_PCH. Forexample, the WTRU 110 should stop the periodic cell update timer. If thenetwork requests a transition to CELL_FACH or if a new configuration isprovided for CELL_PCH, the WTRU 110 should perform actions similar tothose when transitioning to CELL_FACH.

For example, if the IE “Frequency info” is included in the receivedreconfiguration message, the WTRU 110 may select a suitable cell on theprovided frequency. If the if IE “Frequency info” is not included in thereceived reconfiguration message, the WTRU 110 may prohibit periodicalstatus transmission in the RLC, and it may start the timer currentlyreferred to in the standard as T305. If the IE “New C-RNTI” is notincluded in the reconfiguration message, the WTRU 110 can clearvariables C_RNTI, H_RNTI, as well as any stored HARQ information, andmay also reset the MAC-ehs entity. The WTRU 110 may start monitoring thepaging occasions on the selected PICH, and if the IE “UTRAN DRX cyclelength coefficient” is included, it can use this value to determiningthe paging occasions.

Although features and elements are described above in particularcombinations, each feature or element can be used alone without theother features and elements or in various combinations with or withoutother features and elements. The methods or flow charts provided hereinmay be implemented in a computer program, software, or firmwareincorporated in a computer-readable storage medium for execution by ageneral purpose computer or a processor. Examples of computer-readablestorage mediums include a read only memory (ROM), a random access memory(RAM), a register, cache memory, semiconductor memory devices, magneticmedia such as internal hard disks and removable disks, magneto-opticalmedia, and optical media such as CD-ROM disks, and digital versatiledisks (DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any other type of integratedcircuit (IC), and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for use in a wireless transmit receive unit(WTRU), user equipment (UE), terminal, base station, radio networkcontroller (RNC), or any host computer. The WTRU may be used inconjunction with modules, implemented in hardware and/or software, suchas a camera, a video camera module, a videophone, a speakerphone, avibration device, a speaker, a microphone, a television transceiver, ahands free headset, a keyboard, a Bluetooth.RTM. module, a frequencymodulated (FM) radio unit, a liquid crystal display (LCD) display unit,an organic light-emitting diode (OLED) display unit, a digital musicplayer, a media player, a video game player module, an Internet browser,and/or any wireless local area network (WLAN) or Ultra Wide Band (UWB)module.

1. A method implemented by a wireless transmit/receive unit, the methodcomprising: sending, by the WTRU, a Radio Resource Control (RRC)Connection Request message, prior to a cell reselection; performing thecell reselection to a reselected cell; receiving by the WTRU,broadcasted system information regarding the reselected cell;determining, by the WTRU based on the received system information,whether or not the reselected cell supports or does not supportreception over a high speed downlink shared channel (HS-DSCH);configuring the WTRU to use the HS-DSCH, on condition that thereselected cell supports HS-DSCH; sending, by the WTRU to the reselectedcell, a new RRC Connection Request message; and receiving, by the WTRU,a RRC Connection Setup message over the HS-DSCH.
 2. The method of claim1, wherein the determining of whether or not the reselected cellsupports or does not support reception over the HS-DSCH is based onwhether HS-DSCH common system information is included in or excludedfrom the broadcasted system information.
 3. The method of claim 1,wherein the determining of whether or not the reselected cell supportsor does not support reception on the HS-DSCH is further based on whethera value of a variable HS_DSCH_RECEPTION_OF_CCCH_ENABLED is set to TRUE.4. The method of claim 1, further comprising: setting aHS-DSCH_RECEPTION_OF_CCCH_ENABLED variable to FALSE on a condition thatreception over the HS-DSCH not supported.
 5. The method of claim 1,wherein: the sending of the new RRC Connection Request message includesan Initial UE identity information element (IE) set to a value of avariable INITIAL_UE_IDENTITY; and the receiving of the RRC ConnectionSetup message including the value of the Initial UE identity informationelement equal to the value of the variable INITIAL_UE_IDENTITY.
 6. Themethod of claim 1, wherein the receiving of the broadcasted systeminformation regarding the reselected cell includes receiving the HS-DSCHcommon system information of the SIB 5 or SIB 5bis.
 7. The method ofclaim 1, further comprising: checking a value of V300; and determiningthat the value of V300 is equal to or smaller than N300.
 8. A WirelessTransmit/Receive Unit (WTRU), comprising: a receiver; a transmitter; anda processor in communication with the receiver and the transmitter, theprocessor configured to perform a cell reselection to a reselected cell,wherein: the transmitter is configured to send a Radio Resource Control(RRC) Connection Request message prior to the cell reselection, thereceiver is configured to receive broadcasted system informationregarding the reselected cell, the processor is configured to determine,based on the received system information, whether or not the reselectedcell supports or does not support reception over a high speed downlinkshared channel (HS-DSCH), the transmitter is configured to send to thereselected cell, a new RRC Connection Request message, and the receiveris configured to receive a RRC Connection Setup message over theHS-DSCH, on condition that the reselected cell supports HS-DSCH.
 9. TheWTRU of claim 8, wherein the processor is configured to determinewhether or not the reselected cell supports or does not supportreception over the HS-DSCH based on whether HS-DSCH common systeminformation is included in or excluded from the broadcasted systeminformation.
 10. The WTRU of claim 8, wherein the processor isconfigured to determine whether or not the reselected cell supports ordoes not support reception on the HS-DSCH further based on whether avalue of a variable HS_DSCH_RECEPTION_OF_CCCH_ENABLED is set to TRUE.11. The WTRU of claim 8, wherein the processor is configured to set aHS-DSCH_RECEPTION_OF_CCCH_ENABLED variable to FALSE on a condition thatreception over the HS-DSCH not supported.
 12. The WTRU of claim 8,wherein: the processor is configured to generate the new RRC ConnectionRequest message including an Initial WTRU identity information element(IE) set to a value of a variable; and the receiver is configured toreceive the RRC Connection Setup message including the value of theInitial WTRU identity information element equal to the value of thevariable.
 13. The WTRU of claim 8, wherein the receiver is configured toreceive the broadcasted system information including HS-DSCH commonsystem information of the SIB 5 or SIB 5bis.
 14. The WTRU of claim 8,wherein the processor is configured to: check a value of V300; anddetermine that the value of V300 is equal to or smaller than N300.